At one point in the ambiguous trailer for "Side Effects," Catherine Zeta-Jones' character says "Everybody knows everything." In fact, the opposite is true when it comes to director Steven Soderbergh's new pharmaceutical thriller, and that's just fine with distributor Open Road Films.

The auteur director and star-studded cast — which also includes Jude Law, Rooney Mara and the red-hot Channing Tatum — assures it won't go unnoticed when it opens Friday in about 2,600 theaters. But Soderbergh's handling of the relentlessly twisting plot scripted by Scott Z. Burns, with whom he teamed on 2011's "Contagion," defies quick description. It also presents a conundrum: How do you market a film filled with surprises without tipping the surprises or, for that matter, the fact that the film is filled with surprises?

"We knew going in that was going to be a challenge," Open Road Film's president of marketing Jason Cassidy told TheWrap. "But we also knew we had a quality film here, a smart, edgy thriller that would be a very fun ride for audiences — and the less they knew going in, the more fun it would be."

In “Side Effects,” Emily (Mara) and Martin (Tatum) are a successful New York couple whose world unravels when a new drug prescribed by Emily's psychiatrist (Law) has unexpected side effects. Suffice to say, that's just part of the puzzle.

Reviewers, who have had to walk the fine line between describing the film and spilling too much, have helped with the selling of the film, Cassidy said.

"They've generally been very positive and have enjoyed the ride themselves, and I think to help others have that same experience, they've been careful and that's been great," Cassidy said. Several reviewers have drawn comparisons to the 1987 thriller "Fatal Attraction," and Open Road has embraced that comparison and incorporated those notices into its TV advertising.

Some also have compared it to the 2010 thriller "Black Swan," and Open Road has used that comparison as it seeks to connect with the film's primary target demographic, women 18-49 years of age. The presence of Law and Tatum shouldn't hurt on that front either, Cassidy said.

“Side Effects,” which has been in development for years, was at one point known as "Bitter Pill.” Endgame Entertainment stepped in to finance last year after Megan Ellison's Annapurna Pictures — which was behind the film when Blake Lively was attached to star — pulled out.

Soderbergh slid into the project when he parted ways with Warner Bros. over casting differences on "The Man From U.N.C.L.E." It will be one of his final projects before he begins his much-publicized hiatus from the movie business, and that could be a selling point.

Soderbergh's films tend to be hit-or-miss at the box office, and his biggest box office successes have come with Warner Bros. Last year's low-budget male stripper film "Magic Mike" — which also starred Tatum — made $113 million for Warner Bros. But the action film "Haywire," released earlier last year, was a bust for Relativity taking in just $19 million.

Early tracking has "Side Effects," which was made for about $30 million, opening at around $10 million, or about half of what the week's other wide opener, the comedy "Identity Thief," is expected to do.

"We think it's going to play strongly for some time," Cassidy said, "particularly with the reviews, and if we get the kind of word of mouth from first-weekend audiences that we think we're going to."